Supporting Information

KNO3-Mediated Synthesis of High-Surface-Area

Polyacrylonitrile-Based Carbon Material for

Exceptional Supercapacitor

Yao Li, Yeru Liang*, Hang Hu, Hanwu Dong, Mingtao Zheng, Yong Xiao, Yingliang

Liu*

College of Materials and Energy, South China Agricultural University, Guangzhou

510642, China

E-mail address: liangyr@scau.edu.cn (Y. Liang), tliuyl@scau.edu.cn (Y.L.),

Tel. and Fax: +86 020 85280319.

Supporting Information Contents:

Number of pages: 14

Number of figures: 11

Number of tables: 5

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Figure S1. XPS spectra of the samples.

Figure S2. (a) SEM image (b) N2 adsorption–desorption isotherm of the sample based

on the carbonization of PAN with only the addition of KNO3 and without the use of

KOH. Inset in (b) shows its pore size distribution.

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Figure S3. (a) GCD and (b) CV curves of the control sample in a three-electrode

system by using 6.0 M KOH aqueous solution as the electrolyte. Comparison of (c)

GCD curves at 0.5 A g-1 and (d) CV curves at 200 mV s-1 for PPC and control sample.

Figure S4. (a) GCD and (b) CV curves of the control sample in a coin-type

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supercapacitor by using 6.0 M KOH aqueous solution as the electrolyte.

Figure S5. Capacitance comparison of the samples at various current densities in a

coin-type supercapacitor by using 6.0 M KOH aqueous solution as the electrolyte.

Figure S6. Specific volumetric capacitances of PPC and control sample in a coin-type

supercapacitor by using 6.0 M KOH aqueous solution as the electrolyte.

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Figure S7. Cycling stability test of the PPC in a coin-type supercapacitor by using 6.0

M KOH aqueous solution as the electrolyte.

Figure S8. Ragone plots of the samples in coin-type supercapacitors by using 6.0 M

KOH aqueous solution as the electrolyte.

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Figure S9. GCD curves of the control sample in a coin-type supercapacitor by using

1.0 M Na2SO4 aqueous solution as the electrolyte.

Figure S10. CV curves of the control sample in a coin-type supercapacitor by using

1.0 M Na2SO4 aqueous solution as the electrolyte.

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Figure S11. Specific volumetric capacitances of PPC and control sample in a coin-

type supercapacitor by using 1.0 M Na2SO4 aqueous solution as the electrolyte.

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Table S1. BET surface areas, pore volume, and preparation temperature and methods

of the PAN-based carbon materials summarized from literatures.

Ref. Number SBET (m2 g-1) Vt (cm3 g-1) Temperature (oC)

[1] 1000 - 800

[2] 352 1.79 900

[3] 877 0.38 750

[4] 450 0.72 800

[5] 800 1.20 850

[6] 900 1.91 800

[7] 1886 1.20 1000

[8] 3275 1.51 900

[9] 12 - 600

[10] 1160 0.67 1000

[11] 709 1.00 950

[12] 1300 900

[13] 462 0.22 800

[14] 513 0.01 800

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[15] 313 - 800

[16] 627 - 900

[17] 3000 - 800

[18] 3291 2.16 600

This work 3751 2.48 750

Table S2. Parameters of the pore structure of PPC and control sample.

Sample SBET (m2 g-1) Smicro (m2 g-1) Vt (m3 g-1) Vmicro (m3 g-1)

PPC 3751 1751 2.48 0.73

Control sample 3185 2215 1.78 1.07

Table S3. The parameter of the elements in the surface of the samples.

Sample Carbon (at.%) Oxygen (at.%) Nitrogen (at.%)

PPC 88 11 1

Control sample 87 12 2

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Table S4. Comparison of the electrochemical performance for representative carbons

in KOH electrolyte system.

SampleCapacitance (F g-1) Current Density

(A g-1)

Ref.

NumberRef. This Work

Mesoporouscarbon

225 447 0.5 [19]

Ordered mesoporous carbon/graphene aerogel

197 447 0.5 [20]

Nitrogen-doped graphene 250 447 0.5 [21]

Carbon nanospheres 140 447 0.5 [22]

Carbon nanocages 220 447 0.5 [23]

Microporouscarbon nanosheets

210 447 0.5 [24]

Porous carbonnanosheets

250 447 0.5 [25]

Carbon nanosheets 257 447 0.5 [26]

Ordered mesoporous carbon

292 396 1 [27]

Hierarchicalporous carbon

318 447 0.5 [28]

Nitrogen-doped porous carbon nanofibers

202 396 1 [29]

Nanoporous carbon spheres

405 447 0.5 [30]

Porous carbon nanosheets 283 447 0.5 [31]

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Carbon microtubes 292 396 1 [32]

YP-50 189 447 0.5 [33]

Table S5. Comparison of the electrochemical performance for representative carbons

in Na2SO4 electrolyte system.

Sample Capacitance

( F g-1)

Current Density

(A g-1)

Ref.

Number

Seaweed carbon 125 0.2 [34]

3D interconnected carbon 260 0.1 [35]

N/O co-doped carbon 328 0.2 [36]

Carbon sheets 180 0.5 [37]

Porous carbon nanosheets 196 0.2 [38]

Sulfur/carbon spheres 163 0.2 [30]

Porous carbon 178 1.0 [39]

Porous carbon nanosheets 196 0.2 [40]

Egg-Box-Like carbon 181 0.2 [32]

Hierarchical carbon 271 0.8 [41]

Pillared Graphene 89 0.2 [42]

Carbon nanosheets 248 0.2 [43]

RGO/MnO2 paper 204 0.1 [44]

PPC 218 0.5 This work

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